#!/bin/sh
# Ensure that the size of a long-named-symlink is > 0.

# Copyright (C) 2002-2010 Free Software Foundation, Inc.

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

if test "$VERBOSE" = yes; then
  set -x
  du --version
fi

. $srcdir/test-lib.sh

# Determine if `.' is on a local (would non-NFS be sufficient?) file system.
# On at least some NFS implementations, symlinks never take up space,

# So if this is a non-local file system, skip the test.
if df --local . >/dev/null 2>&1; then
  : # Ok.
else
  skip_test_ "\`.' is on a non-local file system"
fi

if df --type=xfs . >/dev/null 2>&1; then
  # At least on Irix-6.5.19, when using an xfs file system,
  # each created symlink (name lengths up to 255) would have a size of `0'.
  skip_test_ "\`.' is on an XFS file system"
fi

if df --type=nfsv3 . >/dev/null 2>&1; then
  # At least on OSF/1 4.0d, when using an nfsv3 file system,
  # each created symlink can end up having a size of 0.
  skip_test_ "\`.' is on an NFS file system"
fi

symlink_name_lengths='1 15 16 31 32 59 60 63 64 127 128 255 256 511 512 1024'
for len in $symlink_name_lengths; do
  name=`seq 1 $len|tr -c x y |head -c$len`
  # Record the names of symlinks that are successfully created.
  ln -fs $name $len > /dev/null 2>&1 \
    && symlinks="$symlinks $len"
done

du -a $symlinks > out || fail=1

# Require that at least one of these symlinks has a non-zero size.
grep '^[1-9]' out > /dev/null || fail=1

Exit $fail
